Abstract: Objective： To evaluate the osteogenic effect of acellular cancellous bone matrix in site preservation of calf. Methods： We select sixteen pure male Beagle dogs, and then randomly divide them into four groups, four in each group. The third and fourth premolars of each Beagle dog were extracted. Then place Calf acellular cancellous bone matrix, Bio-oss bone, Bio-oss bone powder+CGF and blank control in the extraction socket of each group. After the teeth extraction sockets were covered with collagen membrane, and sutured tightly. Beagle dogs were sacrificed at 8 and 12 weeks after operation. The height and width of alveolar bone were observed by CBCT. Bone mineral density (BMD), number of trabeculae and absorption rate of bone materials were measured by ABA bone analysis software. New bone formation, bone remodeling and bone powder absorption were observed and compared by HE and Masson staining, meanwhile the Vascularization, osteoid mineralization, trabecular bone formation and inflammatory reaction were also observed at different stages. Results： There was no statistical significance in alveolar bone height between BABM, Bio-oss bone powder and Bio-oss+CGF tion.(Z=-1.475, P=0.140). The levels of BABM, Bio-oss bone powder, Bio-oss+CGF and blank group were higher at 8 and 12 weeks after operation than those in blank control group. The alveolar bone width before and after operation was lower than that before and on the day after operation at 8 and 12 weeks after operation. The difference has statistical significance(Z=-3.716,P<0.05). There was no statistical difference in bone height and width absorptivity between the acellular cancellous bone matrix group, the Bio-oss group and the Bio-oss+CGF group at 12 weeks after tooth extraction. Histomorphology showed that the new bone formation rate in the Bio-oss+CGF group and the acellular cancellous bone matrix group at 8 weeks was higher than that in the Bio-oss group. Conciusion: Calf acellular cancellous bone matrix can effectively maintain the height and width of alveolar bone and promote the early formation of alveolar bone during the preservation of extraction socket.

Key words: CGF, Bio-oss bone meal, calf acellular cancellous bone matrix, site preservation